Move font data to a subfolder

Marlin/src/core/language.h

Marlin/src/lcd/dogm/fontdata/fontdata_6x9_marlin.h

Marlin/src/lcd/dogm/fontdata/fontdata_ISO10646_1.h

Marlin/src/lcd/dogm/fontdata/language_data_an.h

Marlin/src/lcd/dogm/fontdata/language_data_bg.h

Marlin/src/lcd/dogm/fontdata/language_data_ca.h

Marlin/src/lcd/dogm/fontdata/language_data_cz.h

Marlin/src/lcd/dogm/fontdata/language_data_da.h

Marlin/src/lcd/dogm/fontdata/language_data_de.h

Marlin/src/lcd/dogm/fontdata/language_data_el-gr.h

Marlin/src/lcd/dogm/fontdata/language_data_el.h

Marlin/src/lcd/dogm/fontdata/language_data_en.h

Marlin/src/lcd/dogm/fontdata/language_data_es.h

Marlin/src/lcd/dogm/fontdata/language_data_eu.h

Marlin/src/lcd/dogm/fontdata/language_data_fi.h

Marlin/src/lcd/dogm/fontdata/language_data_fr.h

Marlin/src/lcd/dogm/fontdata/language_data_gl.h

Marlin/src/lcd/dogm/fontdata/language_data_hr.h

Marlin/src/lcd/dogm/fontdata/language_data_it.h

Marlin/src/lcd/dogm/fontdata/language_data_jp-kana.h